This invention relates to feedtube protectors for food processors, and more particularly to such protectors which employ first and second food passageways and first and second food pushers each of which may be locked while the other is in use in order to enable the use of a plurality of different size food passageways in a protector which must be properly positioned on the food processor to enable the food processor to operate for protecting the user and the food processor from injury.
Food processors of the type to which the present invention is applicable have a working bowl with a motor driven shaft projecting upwards into the bowl on which various selected rotary food processing tools can be engaged to be driven by the shaft for performing various food processing operations in accordance with the desires of the user. A detatchable cover is secured over the top of the bowl during use. The cover includes a feedtube having a mouth that opens downwardly through the cover into the top of the bowl. The food items to be processed are placed in this feedtube and are then manually pushed down through the feedtube into the bowl by means of a removable food pusher which is adapted to slide down in the manner of a plunger through the feedtube. Further information with respect to such food processors may be obtained by reference to U.S. Pat. Nos. 3,892,365--Verdun; 3,985,304--Sontheimer; and 4,127,342--Coggiola.
The rotary tools used in food processors are driven by relatively poweful motor drive arrangements and have the capability of causing injury to a finger or hand if the user could inadvertently bring a hand into contact with the motor driven tool. For this reason, a bowl safety cover feature is incorporated into these units which requires that the cover be firmly locked onto the bowl in normal operating position before the motor will operate. This requirement is achieved by making the cover which locks rotationally to the bowl with a projection or member which causes the closing of the switch carried in the housing only when the cover is properly locked in its normal operating position on the bowl. However, this still may not prevent injury to the hand if it were inserted down through the feedtube large enough to accommodate receipt of a hand. Accordingly, the feedtube is deliberately designed in terms of shape, cross section and height, i.e. it is relatively tall and narrow, to make it impossible for an adult to inadvertently insert the hand sufficiently down into the feedtube to touch the rotating tool located in the upper portion of the working bowl. In addition, a food pusher is provided which is insertable into the feedtube for feeding the food items down into engagement with the food processing tool.
The size and shape limitations of the feedtube were overcome by U.S. Pat. No. 4,226,373 to James Williams while maintaining the safety features by providing a feedtube protector the form of an outer sleeve which carries an actuator for enabling the machine operation only when the sleeve is properly positioned over the feedtube. This sleeve has associated therewith a movable food pusher captured by the sleeve and mounted for movement within the sleeve. When the cover is positioned on the bowl and this sleeve is mounted over the feedtube, the food pusher is manually movable within the passageway in the feedtube, and the acutator on the sleeve is operatively associated with the control means of the food processor to permit operation of the motor drive. Accordingly, inadvertent insertion of a hand or a foreign object into the feedtube is prevented when the tool is being driven. By virtue of the arrangement described in Williams, the feedtube can be safely shortened and have a larger cross-sectional area so that large items can be inserted whole into the feedtube.
In Williams application Ser. No. 500,327 entitled SINGLE VERTICAL MOTION FEEDTUBE PROTECTOR AND ACTUATOR FOR A FOOD PROCESSOR, the loading of the feedtube protector described in the aforesaid U.S. patent to Williams is enhanced in enabling a single upward or downward motion of the feedtube protector when properly aligned on the feedtube to actuate the motor drive of the food processor. As will be apparent with a food pusher which is captivated and completely blocks the feedtube when the outer sleeve is positioned thereon, the feedtube protector must be removed to load the feedtube. In some cases, for example, for processing narrow elongated food items such as carrots, cucumbers, pepperoni, celery, zucchini etc., a smaller feedtube is provided inside the larger captivated food pusher, with the smaller feedtube having dimensions and proportions which would prevent the entry of the hand therein i.e., a long narrow passageway in cylindrical form. Thus, a separate food pusher is provided for the second smaller passageway which is operated without removing the outer sleeve from operative engagement with the control means of the food processor. However, when utilizing a food pusher in the second or smaller food passageway, the pushing of food down toward the operating blade could put pressure on the underside of the larger captivated food pusher thereby elevating the captivated food pusher and allowing the food which is to be processed to ride up above the rotating blade and into the larger feedtube passage without being processed and/or injected into the bowl. Accordingly, it would be desirable to lock the captivated food pusher to the outer sleeve when it is not in use, so that the small food pusher and the food processor would function properly when the smaller feedtube is being used.